Or, you can run a pull saw (or sand paper glue onto a wood atrip) between the gap. Just make sure the two panels are firmly clamped.

: Hi
: I am building a stitch and glue tender as a trial run for my boatbuilding
: skills. My question is really simple; do I have to plane the edges of the
: 1/4 inch ply so that each edge butts accurately against its adjoining
: piece. Alternatively can I just leave them square and rely on the glue and
: fibreglass strips to fill in the gaps.